Flex row class should column on mobile.

frontend/styles/positioning.scss

@@ -1,3 +1,5 @@
+@import "@/styles/media-queries.scss";
+
 .flex {
   display: flex;
 
@@ -7,6 +9,10 @@
 
   &.row {
     flex-direction: row;
+
+    @include mobile {
+      flex-direction: column;
+    }
   }
 
   &.wrap {